Extruder-Print head PTFE tube broke
Hello,
I've been printing 6-7 kg of PETG with my Mini+ over the last year without any troubles.
Last week I ordered some PLA for a change and yesterday I tried my first print.
Once the print started I noticed the extruder gear skipping (at 215°, weird) and tightened the tension screw a little more.
All seemed well but when I returned 5 minutes later the PTFE tube connecting the extruder motor and print head had broken on the extruder side.
I would like to figure out what I did wrong, since this is the first real issue I had with the printer.
It seems like the nozzle might have still had some PETG residues that caused clogging at lower temperatures?
What's the proper procedure when you switch from PETG to PLA?
Cheers
Best Answer by BogdanH:
Your guessing is right: there are PETG remains in hotend, which block the extrusion (extruder starts to click, and if tension is high enough, pulls PTFE tube out).
When I change from high temperature filament (PETG) to lower temperature filament (PLA), then my procedure is:
1. Unload PETG filament
2. Load PLA filament, but I choose PETG in menu (PLA is loaded at high temperature and so PETG remains are purged out)
3. Unload PLA filament.
4. Load PLA filament again -this time I choose PLA in menu.
Btw. if you have stock heatbreak, then PTFE tube inside heatbreak probably shrunk because of high (PETG) temperature. I recommend you disassemble hotend, clean it and replace PTFE tube inside. If you don't do that, then above process (1-4) won't help.
RE:
Your guessing is right: there are PETG remains in hotend, which block the extrusion (extruder starts to click, and if tension is high enough, pulls PTFE tube out).
When I change from high temperature filament (PETG) to lower temperature filament (PLA), then my procedure is:
1. Unload PETG filament
2. Load PLA filament, but I choose PETG in menu (PLA is loaded at high temperature and so PETG remains are purged out)
3. Unload PLA filament.
4. Load PLA filament again -this time I choose PLA in menu.
Btw. if you have stock heatbreak, then PTFE tube inside heatbreak probably shrunk because of high (PETG) temperature. I recommend you disassemble hotend, clean it and replace PTFE tube inside. If you don't do that, then above process (1-4) won't help.
[Mini+] [MK3S+BEAR]